Mosquito season in Morgan County, MO: when it starts and ends
Mosquito months in Morgan County
In a normal year mosquito season in Morgan County, MO starts around March 29 and ends around November 3, about 31 weeks.
- Jan
- Feb
- Mar
- Apr
- May
- Jun
- Jul
- Aug
- Sep
- Oct
- Nov
- Dec
What to do in Morgan County, and when
- Start tipping out standing water weekly by March 15.
- Book any yard treatment for late March, ahead of the July peak.
- Repellent can go away after November 3.
- No West Nile cases since 2016, so bites in Morgan County are a nuisance; check window screens.
Morgan County against the rest of MO
Morgan County has the 25th longest season of 115 MO counties, at 219 days against 242 in Pemiscot County and 187 in Crawford County. Its mean temperature is 55.8°F.
- Vernon County: March 29 to November 4 (220 days, 2 WNV)
- Carter County: March 28 to November 2 (219 days, 1 WNV)
- Ste. Genevieve County: March 29 to November 3 (219 days, 0 WNV)
- Texas County: March 29 to November 3 (219 days, 1 WNV)
West Nile in Morgan County
From 1999 to 2025, CDC ArboNET counted 2 human West Nile cases in Morgan County (1 neuroinvasive) across 2 years. The worst was 2015 with 1; the latest was 2015.
More: how the dates are worked out · when mosquitoes go away for the winter.